1. Field of the Invention
The present invention relates to a method for fabricating a display panel, and more particularly to a process-simplified method for fabricating a display panel.
2. Description of the Prior Art
Because of advantages such as compact, lightweight, and power saving, liquid crystal display panels are widely applied in various kinds of electronic products such as smart phones, notebook computers and tablet PCs. The liquid crystal display device becomes the main stream product in the field of flat televisions while the technology of large size liquid crystal display panels develops rapidly.
In the liquid crystal display panel, a display matrix is mainly applied to provide display functions. The display matrix is composed of a plurality of sub-pixels arranged in an array configuration. Each of the sub-pixels includes a thin film transistor unit, a storage capacitor unit, and a liquid crystal capacitor unit. According to the definition of different semiconductor materials, the thin film transistor units are generally classified in three major groups, which are amorphous silicon thin film transistor (a-Si TFT) unit, poly silicon thin film transistor unit, and oxide semiconductor thin film transistor unit. The amorphous silicon thin film transistor unit cannot be good enough to satisfy requirements of foreseeable high performance display devices, because the electrical mobility of the amorphous silicon thin film transistor, which is mainly determined by material properties of amorphous silicon, cannot be effectively enhanced. The electrical mobility of the poly silicon thin film transistor unit is much better because of material properties of poly silicon. However, because of process issues such as worse uniformity, which is mainly generated by crystallization processes applied to large size substrates, the poly silicon thin film transistors are mainly applied in small size display devices. The oxide semiconductor material in the oxide semiconductor thin film transistor unit is generally amorphous, and the electrical mobility of the oxide semiconductor thin film transistor unit, which is generally 10 times higher than the electrical mobility of the amorphous silicon thin film transistor unit, may satisfy the requirements of the foreseeable high performance display devices. There are liquid crystal display panels employing oxide semiconductor thin film transistor units in the market accordingly.